Pulverizing blade cluster



FIG 7 F. D. LARsoN PULVERIZING BLADE CLUSTER Filed April s, 195o FIG 3FIG 6 III IJVENTOR.

FORRE'ST D. I ARSON Y ATTORNEY Patented Aug. 19, 1952 OFFICE PULVEIZINGBLADE CLUSTER Fairies-t n.. Lai-sen, Anoka, Minn., assigner to v PaperCalmens'oii & Co., a corporation of Minf Application April 8, 1950,Serial No. 154,77'l

. 1 y This invention relates to pulverizing bladesor hammers for use inhammer mills or the like, and particularlyfto a clusterof such blades orhammers which is adapted to bemounted in various positions in themachine in order to make all of the several Working edge surfacesreadily :and selectively'available f or performing the pulveriz'ingfunctions of the machine.

It is an object of my invention to provideV a cluster o f elongated flatvb lades which is readily reversible, end for endyas aunit in.the-pulverizingf` machine, without separatingthev individual blades onefrom another. Y, A particular object is` to provide improved means forjoiningthe several blades of a cluster .togetherasa unit or group inwhich the several blades are resiliently heldapart in spaced,substantially parallel relation one to f another whereby limited lateralvibration of the individualbladesis permittedinoperation.

A further object is to provide a cluster of substantially oblong,symmetricalV blades which are connected together and spaced'a-part onefrom another by centrally located `spacing and fastening means so thatthe-cluster'is in `balanceV when in vany of the several` positionsA inwhich it'm'ay be used in a pulverizing` machine. Y

Another object is toiprovide'readily detachable means for connectingtheseveral blades of a cluster together for installation and use as a unit,the connecting means being so fastened to the blades as to permitseparation of the individual blades quickly and easily when thereplacement of one or more of them or rearrangement of them in thecluster becomes necessary or desirable. j

- -The invention also includes' certain other novel features ofconstruction which will be pointed out in the following specificationand claims'.

In the accompanying drawing, a preferred embodiment of my invention isillustrated byway of example. and not for the` purpose of- Iimitation.

' Referring tothe drawing: i

Figure 1 is a fragmentary part side elevational and part sectional viewshowing one of my improved clusters mounted on the rotor of a hammermill or like pulverizing machine;

Fig. 2 is a fragmentary section taken on the line 2 2 of Fig. 1;

Figs. 3 and 4 are side elevational and end views respectively on anenlarged scale showing the pin for connecting the blades together;

Fig. 5 is a side elevational View showing one of the blades for thecluster;

sciaim-s. (c1. 24a-e195) Fig. 6 is a central longitudinal section takenon the line 6--6 of Fig. 5;

Figs. 7 and 8v are respectivelyv enlargedside elevational and end viewsofone of the blade spacing members, and n Figs. 9 and 10 are end-elevational and side views respectively of one of the spring clips forconfining thel blades and spacers on the connecting Din.

The illustrated cluster comprises a series of similar, flat, oblongblades II ofjcase hardened steel, each having substantially parallel,longitudinally extending working edge surfaces I2. A pair of vcircularopenings I3 is formed in each blade and either of these openings isadapted to` receive a supporting shaft I4 carried by the rotor of thepulverizing machine indicated generally by the numeral I5. The blades,as thus far described, a-re of the common type adapted'to be mounted inthe pulverizing machine in various positions in order to lutilize eitherendportion of either ofthe Working edge surfaces I2 as'the leadingimpact edge vportion ofthe blade.

Formed centrally in each of the blades- II is an: aperture I6 adaptedtoreceive va pin or like member .for connecting the blades together. Theaperture I-G- is L centrally disposed with reference to opposite endsand opposite sides of the blade and is preferably non-circular in shapecorresponding to that of` the pin for connecting' the blades together;A. pin I'I is formed to-fitin the several apertures I 6gof the bladesfor connecting themtogetherand `the blades are spaced apar-t onefromanother along the pin by spacing n iefmbers4 I8 vwhicharef connedon thepin. These spacing membersy are preferably oonstructed-V from springwire andflike springI lock washers, have end portions I9whicharefnormally offset laterally one-from `the other as best shown inFig. 8. Near-'each end, thepin Il has an 4annular grooveadapted. tofreceive a spring clipv ZIJ.` The clipsfffare yforcibly sprung into thegrooves gli to confine the'several blades on the pin by engagement withthe outer sur-faces of the end blades of the cluster. By reason of theresiliency of the several spacing members I3 which are compressed whenthe several blades are assembled on the pin, the blades, spacing membersand locking clips 20 are held under lat-- eral compression in theiinished assembly. Further, by reason of the resiliency of the spacingmembers I 8, the several blades of the cluster may be sprung to or fromone another to a limited degree or vibrated laterally in operation.

The several openings I3 near the respective n 3 ends of the blades areheld in alignment one with the others and the several blades areprevented from rotating one relative to another on the pin I1 by reasonof the interlocking of the pin I'I in the blade apertures I6. It willthus be apparent that the hammer cluster assembly shown in Figs. 1 and 2may be handled, installed and adjusted in the machine'as a unit and itoperates as such in the machine. The cluster is free to oscillate aboutthe axis of the supporting shaft I4 and the lower or outer end of thecluster extends closely adjacent to the forami inous plate or screen 22through which the pul'- "4 The number, thickness and spacing of theblades which are held together as a clustered unit may be varied betweenwide limits to suit the particular machine with which it is to be used,the character of the material to be pulverizedand the sizes to which thematerials are to be reduced. Having described my invention, what I claimas new and desire to protect. by Letters Patent is: 1. For a pulvrizing.machine, the combination of a series of similar flat lelongatedv bladeseach Ahaving a plurality of Working edge surfaces symmetrically disposedin relation to a longitudinal axis of the blade and each formed with averized material is passed in the operation ofthe pulverizing machine.

After a period of operation the leading edges I2 of the several bladesof the cluster become worn as a result of abrasion and impact with thematerial being treated and when the wear has progressed to a detrimentaldegree it is desirable to change the position of the4 cluster byreversing it either edgewise f or 1 end for end. Such changes inposition may be made with a minimum of eifort and loss of time by reasonof my construction. In most instances it is unecessary to separate theindividual blades of a cluster. The supporting shaft I4 is merelywithdrawn from the severalV openings I3 to permit an end for endreversal of the position of the several clusters supported on the shaft.Occasionally, however, it is desirable to remove and replace one or moreof the individual blades of a cluster, without replacing the entirecluster, and when this is to be done the cluster, after removal from themachine, may be disassembled or taken apart merely by the removal of oneof the spring clips 20.

For some types of machines where short blades are required,Y the pinconnecting the several blades together may be located nearer one end ofthe blade than the other. Where the need for separation of theindividual blades of a cluster is not likely to develop, the springclips may be omitted and the ends of the pinv I'I may be merely peenedover the adjacent surface of the outer blades of the cluster.

Since in many hammer mills a large number of clusters or groups ofblades are used and readjustment of blades is required frequently, ifthe machine is in continuous use, it will be evident that losses inoperating time and the cost of the readjustment or service Work on themachine are important items in the economics of operation. Importantsavings in maintenance costs and in the time lost in interruptedoperation are obtained by the use of my clusters which are removable andreversible as units quickly and easily. An important factor in suchsavings is they time saved in balancing the readjusted blades. Mycluster is always in balance due to the central location of the bladeconnecting means. The efficiency of the pulverizing operation is alsoimproved and lodging of the pulverized or unpulverized material betweenthe blades is minimized by providing for limited lateral vibration ofthe in dividual blades.

.centrally located, non-circular aperture, a pin fitting in the severalapertures for connecting said blades together and for retaining themagainst relative rotation on said pin, a spring washer conned on saidpin between adjacent blades to resiliently space said blades one fromanother and means engaging the outer blades of said series for conningthe blades andwashers on said pin. j

2. The combination as dened lin *claim 1 in whichsaid pin is formed nearat leastV one of its ends with a recessadaptedfto receive a spring clipand in which said means for engaging the outer blades of said seriesinclude a'spring clip removably engaging "said pin in said recess andheld under lateral compression by said spring washers. `5

3.' For a pulverizing machine, a series of simllar elongated bladeseach'having a, plurality of working edge surfaces symmetrically disposedin relation to a longitudinal axis of the blade and each formed with Vacentrally located aperture and a pair of openings spaced along said axisat opposite sides of said aperture, a pin tting'in said apertures in theseveral blades for connecting them together, spacing "washersinterposedbetween the several blades and confined on said pin and means engagingthe outer lblades of said series for confiningthei blades and 'washerson said pin, said blades-being fixed against rotation one relative toanother on said pin to substantially align the pairfvof openings in eachblade with the corresponding openings in theA other blades and thealigned openings being adapted to receive a shaft for suspending theblades as a cluster unit in a pulverizingV machine. Y

1 FORR'EVST D. LARSON.

REFERENCES QCITED The following references vare of record in the me ofthis patent:

UNITED STATES 'PATENTS

